Intersections

Intersections are planned points of conflict on the roadway system. This includes U.S. and state highways, county roads, and local streets. Motorized and non-motorized users are crossing paths as they travel through or turn from one route to another. Intersections are a priority emphasis area in the Illinois SHSP and represent over 25 percent of the severe injury and fatal crashes on all public roads. Turning and angle crashes are the predominant type of severe crash occurring at intersections. Signalized intersections operate differently than unsignalized intersections and depending on if the intersection is rural or urban, unique challenges need to be considered. A wide variety of safety infrastructure strategies include alternative geometric designs and traffic control devices.

Flashing Yellow Arrows (FYA). Failure to yield to oncoming vehicles is a common cause of angle and turning crashes. The modification of traffic signals to include FYA provides more guidance to the motorist to allow for turning at an intersection while yielding to oncoming vehicles. The addition of FYA can improve the safety performance of an intersection by over 25 percent while maximizing the traffic flow through an intersection. See the attached video for more information.

Roundabouts. Eliminating conflict points and reducing the vehicle speeds can significantly reduce severe crashes occurring at intersections. Roundabouts are an alternative geometric design that achieves this.